CVE-2023-53558: 
Linux Kernel vulnerability analysis and mitigation

A vulnerability in the Linux kernel has been identified and assigned CVE-2023-53558. The issue involves the rcu-tasks subsystem where pr_info() is called with rtp->cbs_gbl_lock spin lock locked. This vulnerability was recently published to the CVE List and has been included within the NVD dataset as of October 4, 2025 (NVD).

The vulnerability occurs in the Linux kernel's rcu-tasks subsystem where pr_info() is called with rtp->cbs_gbl_lock spin lock locked. Because pr_info() calls printk() that might sleep, this results in an invalid wait context bug. The issue manifests in the cblist_init_generic() function, where the lock state creates a potential deadlock situation. The technical trace shows this occurs during the kernel initialization process, specifically in the serial8250_console_write function (NVD).

When triggered, the vulnerability results in an invalid wait context bug in the Linux kernel. This can lead to system instability and potential kernel panics, as demonstrated by the bug trace showing multiple lock contentions in the kernel's console and RCU subsystems (NVD).

The vulnerability has been resolved by moving the pr_info() call so that it is executed without rtp->cbs_gbl_lock being locked. A patch has been developed to address this issue by restructuring the lock handling in the affected code (NVD).